Shuffle elements in list

This example will show how to shuffle an arraylist using the Collections.shuffle method. The snippet below will use a deck of cards to demonstrate how to randomize position order in list.

Straight up Java

@Test
public void shuffle_a_list_java () {
    
    List<String> deckOfCards = new ArrayList<String>();

    deckOfCards.addAll(
            Arrays.asList(
                "Ace", "2", "3", "4", 
                "5", "6", "7", "8", 
                "9", "10", "Jack", 
                "Queen", "King"));
    
    Collections.shuffle(deckOfCards);
    
    logger.info(deckOfCards);

    assertThat(deckOfCards, containsInAnyOrder(
            "Ace", "2", "3", "4", 
            "5", "6", "7", "8", 
            "9", "10", "Jack", 
            "Queen", "King"));
    
}

Output

[2, 8, King, 10, 6, Ace, 4, Queen, 7, Jack, 3, 9, 5]